Atmel's ATMega328 8-Bit Processor in 28 pin DIP package. It's like the ATmega168, with double the flash space. 32K of program space. 23 I/O lines, 6 of which are channels for the 10-bit ADC. Runs up to 20MHz with external crystal. Package can be programmed in circuit. 1.8V to 5V operating voltage!Documents: Atmel Datasheets

Resistor Kit - 1/4W (500 total)sku: COM-10969 Resistors are a good thing, in fact, they're actually crucial in a lot of circuit designs. The only problem seems to be that resistors disappear into thin air. The only way to be sure that you're gonna have the resistor you need when you need it is to stock up, and keep them organized. We have just ...

If you've ever wondered how to control the headlight of a car from a microcontroller, a MOSFET is what you need. The RFP30N06LE is a very common MOSFET with very low on-resistance and a control voltage (aka gate voltage) that is compatible with any 3-5V microcontroller or mechanical switch. This allows you to control high-power devices with very...

Simple shift register IC. Clock in data and latch it to free up IO pins on your micro. Check out this tutorial on how to use this product with the 7 Segment LED and Arduino. Thanks Patrick and Mycha!Documents: 74HC595 Datasheet

Faster, cheaper, smaller, better, right? The SN754410 Quad Half H-Bridge is just that. Capable of driving high voltage motors using TTL 5V logic levels, the SN754410 can drive 4.5V up to 36V at 1A continuous output current! Please see datasheet for more information. This is a pin to pin compatible replacement for the L293D.
Datas...

An adjustable potentiometer can open up many interesting user interfaces. Turn the pot and the resistance changes. Connect VCC to an outer pin, GND to the other, and the center pin will have a voltage that varies from 0 to VCC depending on the rotation of the pot. Hook the center pin to an ADC on a microcontroller and get a variable input ...

This is a simple SPDT slide switch - great for use as an ON/OFF button, or just as a general control switch. The pins are spaced by 0.1", so it's breadboard friendly. The switch is rated for 0.3A at 50VDC. This switch is just a bit smaller than our popular SPDT Mini Power Switch, but uses the same pin spacing. Being smaller takes up less PCB s...

Rotary Encodersku: COM-09117This is a 12-step rotary encoder with a nice 'clicking' feel. It's breadboard friendly, and has a pretty handy select switch (by pushing in on the knob). The encoder is different from a potentiometer in that an encoder has full rotation without limits. The unit outputs gray code so that you can tell how much and in wh...

This is a common 555 timer/oscillator from TI. A classic for all of those first year circuits projects where you need to blink an LED, generate tone, and thousands of other great beginning projects. Google around for a huge list of resources and example projects. Features:4.5V to 16V supply8-pin DIP packageTiming from microseconds to hoursAstab...

2 Wire Serial Communication (I2C) EEPROM - The back bone of any microprocessor project. These 8 pin chips need only two wires to communicate and retain their data even with power failure. Use the 256K EEPROM for some serious data storage!Check out the Portuguese Arduino Tutorial and accompanying Windows App, by Daniel Gonçalves.Datasheets:24LC256

This is the new revision of the kit. We switched to a better trimpot and green LED. This is a kit that gives you all of the basic thru-hole components you will need to get started playing with embedded projects. These are the 'bubble gum' parts that we regularly use. A good starter assortment of caps, ICs, regulators, diodes, and good-for-...

EL wire, or electroluminescent wire, is a flexible wire coated in phosphor. Apply the appropriate voltage and it lights up! It looks a lot like a thin flexible neon tube. They come in many bright colors (check below for other colors) and can be driven pretty easily with an inverter. Check below for compatible inverters as well. This particular ...

Digital Potentiometer - 10Ksku: COM-10613 Potentiometers are incredibly useful, whether you're controlling the volume on your stereo or the 'mood lighting' in your room. The problem with traditional potentiometers the fact that your microcontroller doesn't have an easy way to interface with them. Digital Potentiometers solve that problem by all...

Resonators function like crystals, but are a lower cost solution that does not require external caps.
These resonators are +/-0.5% or better from -20C-+80C. These resonators have built-in load capacitors so no external caps are needed.
Documents:
Datasheet

Basic voltage regulators in the TO-220 package. Adjustable regulator can be set from 1.25V up to 25V output with two external resistors.Check out the LM317 calculator for more information.Also, take a look at our Unregulated Power Supply Tutorial! Documents: LM317 Adjustable Regulator : 1.5A Max

There are lots of trimpots out there. Some are very large, some so small they require a screwdriver. Here at SparkFun, we just needed a simple one that worked. This 10K trimmable potentiometer has a small knob built right in and it's breadboard friendly to boot! Perfect for your next LCD contrast adjuster, opamp setting, or volume level. This m...

This is a very common 0.1uF capacitor. Used on all sorts of applications to decouple ICs from power supplies. 0.1" spaced leads make this a perfect candidate for breadboarding and perf boarding. Rated at 50V.
If you need a bunch of these, you can get good bulk discounts on Digikey, part # : 399-4266-ND
Documents: ...

Not sure what crystal you might need? Looking to stock up your parts bin? Get this package of all the most common values as well as some more specialized frequencies for your next project. We include both through-hole and SMD packages. We even include some 22pF capacitors to use with the crystals.
Includes:
1x - ...

If you've ever wondered how to control the headlight of a car from a microcontroller, a MOSFET is what you need. The FQP27P06 is a very common MOSFET with very low on-resistance and a control voltage (aka gate voltage) that is compatible with most 5V microcontroller or mechanical switches. This allows you to control high-power devices with very...

This is a simple, very common rectifier diode. Often used for reverse voltage protection, the 1N4001 is a staple for many power, DC to DC step up, and breadboard projects. 1N4001 is rated for up to 1A/50V.
If you need a bunch of these, you can get good bulk discounts on Digikey, part # : 1N4001-TPMSCT-ND
Documents: Dat...

This is a very common 22pF capacitor. Used with crystals for loading purposes. 0.1" spaced leads make this a perfect candidate for breadboarding and perf boarding. Rated at 200V. Documents: Crystal Oscillator Lecture Sold in single pieces

8 Darlington Arrays in 18-Pin DIP Package part # ULN2803A. Perfect for running relays and high-power devices up to 500mA and up to 50V!
Resources: Nuts and Volts article on Driving High Current Loads
Documents: ULN2803A Datasheet

The MCP3002 has a 10-bit analog to digital converter (ADC) with a simple to use SPI interface. Use this IC if your microcontroller does not have an ADC or have enough ADC lines. A great chip when you need to add additional ADC lines. Features:2.7V to 5.5V supply10-bit resolution8-pin DIP package3 wire SPI interfaceUp to 75,000 samples per secon...